The Specific Aims of the Clinical Core are: 1) To recruit, screen and enroll into research protocols subjects from defined populations; to follow patients prospectively on studies, maintaining close adherence to study procedures (Project I, III and IV); 2) To collect prospective data on the epidemiology and natural history of HSV infection in immunocompetent and immunocompromised (HIV-infected) persons; to obtain clinical specimens required for virologic and immunologic laboratory investigations; and, 3) To develop new clinical techniques for conducting virologic, epidemiologic, and immunologic investigations of HSV infections. The Clinical Core will enroll and follow study subjects enrolled in studies proposed in Project I, Project III and Project IV. The Core is located at the Virology Research Clinic (VRC) at the University of Washington. The VRC has followed . 8,000 subjects in 173 clinical studies. A unique strength of the clinic staff is their ability to recruit, enroll and follow patients with genital HSV infection for prolonged periods of time. The process of enrolling patients into study protocols is standardized, as is collection of specimens. The evaluation and clinical care of subjects with newly acquired or recurrent genital herpes follows established procedures. Several specialized procedures have been developed and tested at the VRC. The protocols for daily collection of swabs of genital secretions and the collection of samples for assaying antibodies and HSV specific T cell from mucosal sites. Invasive and non-invasive methods for obtaining samples for immunologic studies have been developed, e.g., lesional biopsies for studies of cellular immunity. In the last 5 years, the investigations have expanded to include HIV-infected persons. For Project IV, new techniques for non-invasive sampling of lymphocytes from the cervix using cytobrush will be tested. For Project III, partner notification of patients with newly acquired genital herpes will be introduced. A computerized sexual history will be piloted to increase disclosure of high risk behavior. Centralized care of study subjects enrolled in proposed HSV Project Grant studies allows for efficient recruitment, standardized collection of data and assurance that excellent clinical care is provided.